1. Field of the Invention
This invention relates to cameras. More specifically, this invention relates to cameras employing what is commonly known as an electronic shutter.
2. Description of the Prior Art
The term "electronic shutter" has been applied to exposure control systems for cameras in which an electronic timing circuit responsive to scene light is actuated synchronously with the opening of the camera shutter. The timing circuit triggers closing of the shutter after a time has elapsed which is functionally related to scene light conditions. This mechanism has the advantage of high accuracy for both low and high conditions of scene illumination. An example of such an exposure control system appears in Harvey, "Photographic Apparatus, " U.S. Pat. No. 3,680,453.
It is known to energize an electromotive source or solenoid to start an exposure interval and to re-energize the same source to terminate the exposure interval. See, for example, Bowers, "Electrically Actuated Camera Shutter,"U.S. Pat. No. 1,444,365.
It is also known to energize an electromagnet to start an exposure interval after a predetermined time delay. An electronic timing circuit re-energizes the electromagnet to terminate the exposure interval. See Minoru Suzuki et al, "Automatic Light Responsive Shutter Timing Mechanism," U.S. Pat. No. 3,349,678
In Bestenreimer, "Photographic Camera, " U.S. Pat. No. 3,385,187, a camera is disclosed having an electromagnet controlled lever interacting with a shutter member to establish the size of an exposure aperture. Cocking of the shutter member energizes the electromagnet. De-energization of the electromagnet locks the shutter member and fixes the size of the exposure aperture. Re-energization of the electromagnet releases another member to terminate the exposure interval.